Customise the panel without losing code on update

how would you go to customise the root page of the panel (it would suffice to change the css and hide some elements in the php template), without losing all this on the next update of kirby?

css wise i can just place the css file in the assets folder, but what about changing the php logic?

What exactly do you want to change?

redesigning the root panel page and adding custom modules — or take out some of the modules loaded in a cleaner way than set them to display: none.

You can hide any Dashboard widget via the config, no need to touch the source code?

c::set('panel.widgets', array(
  'site' => false,
  'pages' => false,
  'history' => false,
  'account' => false
));

You can also do this based on user roles using permissions.

very nice, thank you!